chore(deps): update grafana/grafana docker tag to v12.1.2 (#1590)

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This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [grafana/grafana](https://redirect.github.com/grafana/grafana) | patch
| `12.1.1` -> `12.1.2` |

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examples/example-exemplars-tail-sampling/docker-compose.yaml

@@ -59,7 +59,7 @@ services:
     command:
       - --config.file=/config.yaml
   grafana:
-    image: grafana/grafana:12.1.1@sha256:a1701c2180249361737a99a01bc770db39381640e4d631825d38ff4535efa47d
+    image: grafana/grafana:12.1.2@sha256:d709daa8c978ac6064865086500f16102deb560956177d012a21b529c627c65c
     network_mode: host
     ports:
       - "3000:3000"

examples/example-native-histogram/docker-compose.yaml

@@ -18,7 +18,7 @@ services:
       - --enable-feature=native-histograms
       - --config.file=/prometheus.yml
   grafana:
-    image: grafana/grafana:12.1.1@sha256:a1701c2180249361737a99a01bc770db39381640e4d631825d38ff4535efa47d
+    image: grafana/grafana:12.1.2@sha256:d709daa8c978ac6064865086500f16102deb560956177d012a21b529c627c65c
     network_mode: host
     volumes:
       - ./docker-compose/grafana-datasources.yaml:/etc/grafana/provisioning/datasources/grafana-datasources.yaml